The reaction of neodymium, europium, or terbium nitrate with cucurbit[6]uril (CB6) in the presence of the alpha-amino acid L-cysteine (L-cys) gives the complexes [Nd(L-cys)(CB6)(NO3)(H2O)4]center dot 2NO(3)center dot 10H(2)O (1) and {[Ln (L-cys)(CB6)(H2O)(5)][Ln (L-cys) (CB6) (NO3)-(H2O)(4)]) center dot 5NO(3)center dot 22H(2)O with Ln = Eu (2) or Tb (3). 2 and 3 only differ from 1 by the presence of two independent metal ions in slightly different environments. In all cases, each metal atom is bound to the bidentate CB6 and the monodentate L-cys molecules, with the latter being in its zwitterionic form. The ammonium group of L-cys is directed away from CB6 and is involved in ion-dipole and hydrogen bonding interactions with the uncomplexed portal of the neighboring molecule, which gives rise to the formation of chiral one-dimensional assemblies of columnar shape.